CVE-2026-124853 is a critical vulnerability in Firefox's Graphics: Text component caused by incorrect boundary conditions, allowing sandbox escape. This flaw was addressed and fixed in Firefox 160 and Firefox ESR 115.45. The vulnerability has a high CVSS score of 9.6, indicating severe impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported. Users should update to the fixed versions to mitigate the risk.